3-Pack TP-Link Deco M4 Whole Home Mesh Wi-Fi System Expired

I'll be another chime in the Deco is a great buy. I had a very expensive velop system go tits up on me after about 7 months (primary base station got stuck in a boot loop). Velop said I could PAY to ship them in for potential coverage under warranty, based on what I read online and just the hassle of it I decided to just move on. Deco was cheap enough that I was willing to throw the bones.

Pros: Easy ability to setup IP Reservation (i.e. static IPs).
Easy pairing/setup out of the box
Easy ability to change "primary" unit, not sure if this really matters but I thought it was a nice touch
Ethernet Back Haul. These units do NOT have dedicated back haul band (hence part of why they are cheaper compared to something like Velop) but if your house is wired for ethernet you can run the backhaul over that instead and create a really fast network in every corner of your home

Negs: No dedicated backhaul on wireless. This results in greatly reduced speed if you are going across multiple HOPS. i.e. you aren't setup in a wheel/spoke but instead a straight line A - B - C where your device is on piece C and it hands to HOP through B to get to primary unit A. More expensive systems have dedicated antenna resources for that backhaul, these cheaper units do not. Less important if you are in a more hub/spoke layout as its less likely you will have multiple hops but something to consider.
No web based admin panel. Common in a lot of mesh units unfortunately but you have to use an iOS or android app to administrate these units which just seems silly.

Otherwise though, a great buy for the price. Wireless performance is fantastic assuming you don't have multiple hops in your mesh layout. If you do think that might occur consider a unit with dedicated wireless back haul (velop tri band for instance). They cost significantly more *but* if you fall into those edge case it makes a huge difference.

The M5 has better 2.4ghz range and performance while the M4 has equal or slightly better 5ghz performance. If your primarily using only 5ghz devices and dont need to control traffic the M4 would be better for some.

The M4 is missing QoS and antivirus features, which the M5 has.

Those are the main differences.

There are arguments for both, don't quote me but I'm fairly sure the newest version took a hit on the fastest WiFi tech, but increased their wireless N speed. Some prefer the low profile of the M5 - personally I think they look like smoke detectors - some hate the vertical space consumed by M4. It's a lot of personal preference and nitpicking from what I've seen, but there is not a significant upgrade in tech and or experience from what I've read / seen.